The invention generally relates to digitally synthesized signal generation with particular application to low frequency power signal generation.
A standard technique for synthesizing a waveform uses a microprocessor or digital signal processor to read a digitized waveform from memory, and then write it to a digital to analog converter (DAC) consecutively at fixed time intervals. This and other similar techniques have several disadvantages, including the use of multiple electronic components for each channel on which a signal is generated. The use of multiple components increases the power consumption, size, complexity, and cost of the system, while decreasing reliability. Moreover, if multiple signals must have a common phase reference, complex multiprocessor synchronization techniques must be used, requiring more circuitry or complicated computer programs. The present invention provides signal generation without these disadvantages.
Recently, companies that control electric power distribution have begun to mandate the monitoring of power line load levels. For example, public utility power companies are beginning to automate power line load monitoring functions traditionally performed manually. However, until this invention, utilities and other institutions have had no way to test completely these monitoring devices. The present invention directly addresses this need by offering the capability of synthesizing power line loading signals for testing and other purposes.